code: def free_overlay(self):
      self.free()
  
file_path: hls4ml/hls4ml/templates/vivado_accelerator/alveo/python_drivers/axi_stream_driver.py
imports: from datetime import datetime
  import numpy
  from pynq import Overlay, allocate
label_desc: Use image node_id 4 for calling the NeuralNetworkOverlay obj's underlying member method code with example usage: obj.free_overlay() without return types